Urine and faecal management devices are known articles of manufacture that are designed to be worn principally by incontinence sufferers and in particular by bedridden patients. Such devices are attached to the natural anal region or artificial anus of the wearer and or uro genital area and are intended to receive entrap and immediately contain urine, faecal material and other bodily discharges.
Such devices as they are mostly known today are designed to be worn by bedridden patients. As such the devices are constituted of a relatively long and narrow tube, at one extremity of which there is an aperture and a skin attachment device upon which an adhesive can be applied.
Examples of these bags are disclosed for example in U.S. Pat. No. 3,577,989, which details a disposable elimination-trapping bag for incontinence sufferers including a container member having an open-top portion, and a flange secured to the container member around the open-top portion. The flange may include a layer of adhesive on its surface as a means of attachment of the bag to the wearer or alternatively discloses the use of elastic straps to attach the bag to the wearer. U.S. Pat. No. 4,784,656 also describes a receptacle for collecting faecal matter from incontinence sufferers. The faecal collector comprises a gasket, conduit means or a cylinder and a receptacle; the receptacle and conduit means are each formed from two sheets of odour barrier thermoplastic film that are heat sealed along their side edges, respectively and the side surface of the gasket is coated with a layer of adhesive; GB 2 152 387, teaches a faecal collector for incontinence sufferers comprising a collection bag and a ring, which is provided with an adhesive. The faecal collector comprises a pair of panels of thermoplastic sheet material joined at their margins to define an elongate bag having an opening at one end. GB 1 078 588 describes a urine collector comprising a liquid proof bag of tube like configuration having an opening surrounded by an attachment means in the form of an adhesive bearing material.
Other types of faecal management bags having a flatter shape are known from EP 245 064. EP 245 064 discloses bags having a front and a rear wall, the front wall containing the aperture and attachment means to the body. The attachment means is a skin compatible water resistant material such as a hydrocolloid and a water insoluble viscose elastic binder.
Due to their typical elongated shape and dimensions, such devices particularly when worn by active wearers, such as infants or non bedridden incontinent adults, can readily twist around the thighs of the wearers and/or can cause the formation of folds and kinks in the devices themselves. Under such circumstances the pressure and stress exerted upon the bag will naturally increase due to the movement of the wearer and the pressure of the wearer's body upon the bag. Consequently, the likelihood that the urine or faecal material once excreted and contained within the bag will be caused to exert pressure upon the attachment means of the device will increase. As a result not only will the storage capacity of the device be detrimentally affected but also more importantly it may result in unintentional detachment of the device from the wearer during use. Such an occurrence is unacceptable causing distressing consequences for both the wearer and the carer.
Hence, it is critical that the urine and/or faecal management devices are designed such that they are securely attached to the skin of the wearer and do not become unintentionally unattached during all circumstances of use.
In order to provide the desired level of adhesion of the device to the wearer, the prior art typically discloses the utilisation of certain adhesives having very high cohesive strengths such as rubber based adhesives and acrylics. These adhesives are then applied as thick layers over the entire surface of the flange of the device to maximise the adhesive force by which the device is secured to the skin of the wearer. Indeed it is apparent that these devices, and in particular the adhesives, have been designed for use on faecal management devices utilised by bedridden patients particularly those having an artificial anus whereby maximum adhesion takes priority over any other criteria such as patient comfort.
However, the adhesive must have a skin compatible composition and not be harsh or aggressive towards the skin or cause skin irritation or inflammation. Also it is preferred if the adhesive is compliant with the skin of the wearer such that maximum skin surface contact between the adhesive and the skin is achieved. Moreover, it is also desirable to provide an adhesive such that the disposal human waste management device can be readily removed from the wearer, without the wearer experiencing any unacceptable pain level. This is particularly important under circumstances, where the device is misplaced, and removal and reapplication of the device once or even a number of times is required and or to ensure the application of such devices on sensitive skin and wearer groups such as infants. However, on the other hand the desired level of adhesion, albeit painless should of course also be maintained during such multiple applications of the device.
The problem of achieving the desired adhesion level is further exacerbated under wet skin conditions. Typically, prior to the placement of the disposable human waste management device, the skin is cleaned and is usually as a result moist. The currently available adhesives, such as hydrocolloids, however often do not immediately strongly adhere to the skin and may need to be held in place until sufficient minimum adhesion occurs. Moreover, the overall adhesive ability of such adhesives tends to be significantly reduced on wet skin surfaces per se, so that the device will typically not remain attached to the skin during wearer if any pressure is exerted onto the device, for example by the movement of the wearer or during the defaecation process. Alternatively adhesives which are able to absorb water and thus immediately adhere to moist skin, tend to absorb water very rapidly and not in a controlled manner such that extended adhesion time is not provided.
Another problem which is associated with adhesives which do not maintain their adhesive strength after exposure to liquids is that not only will the adhesive no longer adhere satisfactorily to skin, it will also no longer adhere to the flange.
Moist and wet skin however is not just a problem which is prevalent at the device application stage, as a significant amount of moisture is also generated during the use of the device from the wearer by perspiration and from the material contained within the disposable human waste device. In addition particularly for the case of urine management devices, small amounts of liquid may be deposited or migrate on to the flange surface without entering the bag cavity. The resulting humid environment naturally further increases when the device is utilised in combination with a diaper. Under such circumstances currently available adhesives typically cannot absorb this moisture and again the adhesive strength is reduced to such an extent that the device will often become detached under exertion of pressure during wear. It is hence very important to provide an adhesive which provides both initial adhesion and maintenance of its adhesive strength on wet skin. Moreover, it is also another important factor for the product performance that the adhesive is also stable to exposure to excess quantities of liquid such as water and in particular urine, so that it will also not loose its adhesive strength under such circumstances.
None of the prior art in the field of faecal management bags however even recognises or addresses the problem of providing these devices with an adhesive which meets these criteria, in particular adhesives which adhere to wet skin and are stable and maintain their adhesiveness even when exposed to excessive amounts of liquid.
The prior art in the general field of adhesives for attachment to the skin is in contrast more developed in the field of articles such as band-aids, plasters and bandages. These articles are however typically applied in an emergency situation, where for example, a cut into the skin of the wearer has occurred and absorption of the body liquids emanating from a wound is desired. In this context performance aspects of the article such as easy application and use of the product, comfortable wear as well as painless removal, and discreteness are again subordinate, to other criteria in this case such as sterility, healing support, and mechanical protection of the wound. Such products typically have poor wet skin adhesion.
Adhesion to wet skin is addressed for example in WO 98/03208 which discloses medical pressure sensitive adhesives which can adhere to dry or wet skin and which comprise a mixture of hydrophilic (meth)acrylate copolymer containing tertiaryamino groups, a hydrophilic (meth)acrylate copolymer containing carboxyl groups, carboxylic acids and a crosslinking system. However this document does not discuss adhesion after exposure to excess liquid. Similarly, WO 97/24149 discloses a polar lipophilic pressure sensitive adhesive comprising a hydrophilic polymer matrix, a plasticizing solution and a surfactant that provides good adhesion to a variety of skin types. In this document the adhesives do not adhere to wet surfaces.
Another field wherein the use of such adhesives has been disclosed is in absorbent such as for example sanitary napkins, as described in for example U.S. statutory invention registration H1602 or WO 96/33683 and WO 95/16424. The latter discloses sanitary articles having a topical adhesive which is applied on the wearer facing side of a sanitary napkin along the entire periphery. WO 96/13238 discloses a topical adhesive which is described in terms of frequency dependency. EP-638 303 discloses the use of a topical adhesive on side cuffs of sanitary napkins in order to keep the cuffs in an upright position. Swiss publication CH-643730 discloses the use of a very long sanitary napkin having chamfered outer edges with a topical adhesive at the four corners of the outer edges in order to provide a topical adhesive area well outside the region of pubic hair growth.
However all of these disclosures typically disclose a product which is designed to be utilised in combination with an undergarment and hence the degree of adhesion actually provided is very low and is not designed to withstand any excessive pressure. Moreover the adhesive is only discussed in general terms or concentrates on the area of application of the adhesive to the article. The nature of adhesive per se other than the basic physical requirements such as pressure sensitivity are not discussed in particular with reference to the chemical composition or the adhesive criteria.
Hence there still exists a need to provide disposable human waste management devices having an adhesive for the secure attachment and painless removal of the device from the skin in-between the buttocks of the wearer so as to be suitable for use of sensitive skin of an infant and it is thus an object of the present invention to provide such a device.
It is another objective of the present invention to provide an adhesive that exhibits an ability to adhere to skin upon reapplication, particularly multiple reapplication for example when the device is misplaced, whilst still allowing painless removal.
It is yet a further objective of the present invention that the adhesive will adhere to moist or wet skin, independent of whether this is direct application of the device onto wet skin, or moisture which is generated on the skin surface during the wearing period of the device. In particular it is an objective of the present invention to provide an adhesive which is liquid stable particularly to water and urine, such that the adhesion properties will not be significantly effected in the presence thereof over the period of wear of the device.
It is another object of the present invention to provide an adhesive which upon removal from the skin of the wearer leaves no residues. It is yet another object of the present invention to provide an adhesive which does not cause a cold or otherwise unacceptable temperature sensation upon application to the wearer.
An additional object of the present invention to provide an adhesive which in combination with the flange material provides flexibility, stretchability and contractability so that it is able to adapt to the contours of the body during all bodily movements and hence be comfortable for the wearer of the device, whilst still having sufficient adhesive capacity to ensure secure attachment during use.
In addition to the above objectives of the present invention it is also desirable for the adhesives to provide additional benefits such as delivery/dispersal of a compound or composition which is beneficial for the skin or for the body in general.
It has now been surprisingly found that the above drawbacks will be substantially alleviated by providing the flange of the disposal human waste management device with an adhesive as defined hereinafter. The adhesive provides secure attachment, is pleasing to the skin upon application, and yet causes no discomfort upon removal and maintains its adhesive strength over the period of wear.
In another aspect of the present invention, the disposal human waste management device with its specific adhesive as defined herein can be advantageously used in combination with a reusable underwear garment or preferably with a disposable diaper.